A method of ascertaining grade length limitation of freeways in mountain terrain is presented. The relationship models between 15 th percentile speeds and grades were built through the surveys and analyses of operatio...A method of ascertaining grade length limitation of freeways in mountain terrain is presented. The relationship models between 15 th percentile speeds and grades were built through the surveys and analyses of operation speeds on 7 typical sections of 3 freeways in mountain terrain. Using 15 thpercentile and 85 th percentile as speed limitations, the methods of determining admitted velocities were put forward according to the grades. Deceleration distances of longitudinal slopeways were analyzed utilizing the theories of vehicle. According to the results of analysis, grade length limitation was loosed. Finally the values of grade length limitation for freeways were put forward. The results could be used as references for freeway design.展开更多
Successful completion of the landscape design work, the implementation on-site is very important besides the prophase design. While in the process of project implementation, what plays an important role is the relatio...Successful completion of the landscape design work, the implementation on-site is very important besides the prophase design. While in the process of project implementation, what plays an important role is the relationship between persons to persons and persons to things, but not just a simple drawing on the paper. This paper summarized some aspects of project implementation of the NOd Xiangjiang in Changsha, and hopes to achieve the designer＇ s desired results when the landscaping project is completed.展开更多
基金Sponsored by the Specialized Research Fund for the Doctoral Program of High Education(Grant No.20030213030)
文摘A method of ascertaining grade length limitation of freeways in mountain terrain is presented. The relationship models between 15 th percentile speeds and grades were built through the surveys and analyses of operation speeds on 7 typical sections of 3 freeways in mountain terrain. Using 15 thpercentile and 85 th percentile as speed limitations, the methods of determining admitted velocities were put forward according to the grades. Deceleration distances of longitudinal slopeways were analyzed utilizing the theories of vehicle. According to the results of analysis, grade length limitation was loosed. Finally the values of grade length limitation for freeways were put forward. The results could be used as references for freeway design.
文摘Successful completion of the landscape design work, the implementation on-site is very important besides the prophase design. While in the process of project implementation, what plays an important role is the relationship between persons to persons and persons to things, but not just a simple drawing on the paper. This paper summarized some aspects of project implementation of the NOd Xiangjiang in Changsha, and hopes to achieve the designer＇ s desired results when the landscaping project is completed.
